64649645605 has 4 divisors (see below), whose sum is σ = 77579574732. Its totient is φ = 51719716480.

The previous prime is 64649645591. The next prime is 64649645629. The reversal of 64649645605 is 50654694646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50654694646 = 2 ⋅25327347323.

It can be written as a sum of positive squares in 2 ways, for example, as 6602862564 + 58046783041 = 81258^2 + 240929^2 .

It is not a de Polignac number, because 64649645605 - 2⁵ = 64649645573 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6464964556 + ... + 6464964565.

It is an arithmetic number, because the mean of its divisors is an integer number (19394893683).

Almost surely, 2^64649645605 is an apocalyptic number.

It is an amenable number.

64649645605 is a deficient number, since it is larger than the sum of its proper divisors (12929929127).

64649645605 is a wasteful number, since it uses less digits than its factorization.

64649645605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12929929126.

The product of its (nonzero) digits is 18662400, while the sum is 55.

The spelling of 64649645605 in words is "sixty-four billion, six hundred forty-nine million, six hundred forty-five thousand, six hundred five".